Winding for electrical apparatus



Feb. 10, 1959 A. GLAssANos WINDING FOR ELECTRICAL APPARATUS Filed Oct. 24, 1957 jig. 4.

United States Patent O 2,873,432 n WINDING FOR ELECTRICAL APPARATUS Andrew Glassanos, Pittsfield, Mass., assigner to General Electric Company, a corporation of New York Application ctober 24, 1957, Serial No. 692,223

, 8 Claims. (Cl. 336-192) i This' invention relates to electrical apparatus, and more in particular to an improved winding construction for stationary electrical induction apparatus such as transformers, reactors, and the like.

The low voltage winding leads of high current electrical induction apparatus, such as transformers adapted to supply electrical furnaces, are frequently comprised of a plurality of parallel conducting bars instead of only one large bar connected to each end of the winding, due to the difficulties involved in connecting and supporting a bar of the dimensions required to carry the full winding current. Since the reactance of the leads is proportional to the spacing between leads connected to opposite ends of the winding, the leads extending from opposite winding ends are preferably alternated rather than grouped in order that the reactance may be minimized by having the effective spacing of the leads as low as possible. That is, the bars generally extend from the winding in a common plane, with each bar connected to one end of the winding being positioned between bars connected to the other end of the winding.

This lead arrangement ordinarily presents no problems in conventional types of furnace transformer windings (e. g. Where the low voltage winding is comprised of a plurality of parallel connected winding sections). Occasionally, however, it is desirable that the low voltage winding comprise a single turn of a sheet of c011- ducting material, with the leads extending from opposite sides of an axially extending gap separating the edges of the sheet which define the ends of the single turn. This type of winding may be generally described as a4 sheath winding. In the past, when such single turn windings were employed, attempts to alternate the bar leads to reduce reactance resulted in complicated and uneconomical bar lead structures, since all of the bars connected to each end of the winding were connected to the winding at one peripheral location.

It is therefore an object ofrthis invention to provide an improved sheath winding for electrical apparatus.

It is also an object to provide a bar lead arrangement for single turn electrical apparatus windings wherein `alternation of leads connected to opposite sides of the winding to reduce lead reactance does no-t result in complicated or uneconomical bar lead structures.

A further object of this invention is to provide a single turn electrical winding comprised of a sheet of conducting material, wherein the gap separating the edges of the sheet which deiine the ends of the single turn is staggered in order that bar leads connected to opposite sides of the winding may be alternated without the necessity for complicated or uneconomicai bar lead structures.

Briefly stated, and in accordance with the preferred aspects of my invention, I provide a winding for an electrical apparatus, such as furnace transformers, the winding comprising a hollow cylindrical conducting member. A gap extends through the member axially from one end to the other thereof, and the ends of the -gap are preferably c ircumferentially displaced. A plurality of radially extending flanges are provided on the cylin drical conducting member on each side of the gap, the flanges ybeing adapted to be connected to bar leads. The gap separating the ends of the winding is preferably stepped, that is, the gap has a plurality of portions extending axially on the cylindrical member joined by at least one circumferentially extending portion.

While the specification concludes with claims particular'ly pointing out and distinctly claiming the subject matter which I regard as my invention, it is believed that the invention will be better understood from the following description taken in connection with the accompanying drawing.

In the drawing:

Fig. l is a perspective view of a sheath winding according to one aspect of my invention, and illustrating the winding disposed about the leg of a magnetic core,

Fig. 2 is a side view of the winding of Fig. 1, and illustrating a plurality of bar leads extending from the winding,

Fig. 3 is a cross-sectional view of the winding of Fig. 2 taken along the lines 3-3,

Fig. 4 is a cross-sectional view of an alternate means of providing flanges on the winding of Figs. l and 2, and

Fig. S is a side view of a modification of the winding of Fig. 2.

Referring now to the drawing, and more in particular to Fig. l, ltherein is illustrated a hollow cylindrical conducting member 10 formed of a sheet of conducting material, and comprising a single turn winding. The winding leg 11 of a magnetic core extends axially through the member 10, and additionalwindings (not shown for the sake of clarity) may also be provided surrounding the core 11.

A gap 12 is provided extending axially through the conducting member 10, and the axial ends of the gap -12 are circumferentially displaced about the member 10. For example, as illustrated in Figs. l and 2, the gap 12 may comprise a plurality of axially extending portions 13 joined by circumferentially extending portions 14. Ra-dially outwardly extending flanges are provided eX- tending from each side of the axially extending portions 13 of the gap 12. As illustrated in'Fig. 3, the ilanges 15 preferably lie in parallel planes to facilitate attachment of leads thereto. The tlanges 1S may be formed from the same sheet of material as the cylindrical member 10, as illustrated in Figs. l and 3, or they may be separate angle shaped members welded or otherwise suitably aillxed to the member 10 as illustrated in Fig. 4.

A plurality of axially extending bars 20 of conducting material (Figs. 2 and 3) are connected to the llanges 1S on one Side of the gap 12, with one bar 20 being connected to each flange, and a plurality of axially extending conducting bars 21 are connected to the flanges 15 on the other side of the gap 12 with one bar 21 being connected to each flange. As illustrated in the drawing, the bars extend in one direction from the ilange to which they are connected, and the bars 20 and 21 are connected to the sides of the ilanges 15 away from the gap 12. The axially extending portions 13 of the gap are spaced circumferentially so that each of the bar leads extending from a ilange on one side of the gap is located between ybars extending from the opposite side of the gap, and the circumferential distance between all of the bars is substantially the same.

lf desired, one or more pairs of bar leads may be connected to more than one Winding flange. Thus, as illustrated in Fig. 5, the ends 30 of the gap 12 are in the same peripheral location and a central portion 31 of the gap is circumferentially displaced fro-m the end portions. The bar leads 32 and 33 joining the uppermost Winding ilanges extend downwardly and also join f 3 the lowermost winding flanges. The remaining bars 34 and 435 join the central lianges. ln this arrangement the sum of the axial lengths of the endmost flanges should `equalthe axiallength of the :central flangein order that the bar Aleads carry equal currents.

Additional steps, which may be connected to additionalbars, may also be provided in this arrangement, if so desired, without departingfrom .the spirit or scope of my invention.

Fromthe preceding disclosure it is seen that the present invention, by circumferentially displacing portions of a gap extending through the winding, has provided means whereby the leads extending from the winding may be alternated to minimize lead reactance without'th'e necessity for complicated lead congurations.

.It will be understood, of course, that, while the forms of the invention herein shown and described constitute preferred embodiments of my invention,iit.isl not intended herein to illustrate all of the possible equivalent forms 4ally through the wall of said cylindrical member, radially extending iianges on ysaid member adjacent axially extendingportions .ofsaid gap, and parallelleads connected to -said iianges.

v2. .An electrical winding comprising a hollow cylindrical conducting member, a gap extending .through the wall of .said cylindrical member, saidgap'having aplurality of portions extending axially of said member and joined by at least one -circumferentially extending portion, "a plurality of radially outwardly extending flanges on ,said member on each side of the axial portions of lsaid gap, and parallel leads 'connected to said flanges.

3. A winding for electrical apparatus comprising a hollow `cylindrical conducting member, a gap extending `axially through said member vfrom one end to the other end thereof, the ends of said gap being circumferentially displaced, and a plurality `of radially extending flanges on said member on each side of said gap, and coplanar parallel leads connected 'to said flanges, with Valternate Vleads being connected' to opposite sides of said gap.

'4. A winding Afor electrical apparatus comprising a hollow cylindrical conducting member, a gap extending axially through said member 'from one end'to the other end thereof, the ends of said gap being circumferentially displaced, anda plurality of flanges extending radially outwardly from said member on each side of said gap, said flanges being circumferentially displaced, and coplanar parallel leads connected to said flanges, alternate leads ibeing connected to opposite sides of said gap.

5. lA* winding for a transformer `comprising a hollow cylindrical conducting member, a lgap extending through said member from one end to the `other end, -t'he ends of said gap being circumferentially displaced, a plurality of ianges-extending radially from said member on each side of said gap, and a conducting lead connected to each of said anges and extending axially of said winding, said flanges being circumferentially displaced so that alternate leads are connected to flanges on opposite sides ofsaidgap. f

6. The winding of claim .5 Vin which the gap has lportions extending ,axially of said member and portions extending circumferentially of `said winding joining the axially extending. portions, :and the flanges extend from said member adjacent the axially extending portions of said gap.

7. A stationary electrical induction apparatus comprising .a magnetic corehaving a winding leg, and a winding Vsurrounding ysaid leg and insulated therefrom, said winding comprising a hollow cylindrical conductingmem- 4ber having a gap extending :between the ends thereof, the 30 ends of vsaid gap Abeing circumferentially displaced, and

.aplurality .of anges extending "radially from said mem- '.beradjacent each side of saidgap.

'8. A stationary electrical induction Yapparatus compris- ,ing a magnetic vcore `having a winding'leg, anda wind- .ing surrounding said leg and insulated therefrom, said winding `comprising ahollow cylindrical -conductingmernlber having a gap extending from one end to the other end thereof, the Yends of said gap being circumferentially displaced, a Aplurality of anges extending radially from saidlmember on each side of said gap, and a bar lead fextending axially of said `winding from each flange, Ythe flanges being circumferentially displaced so that alter- Vnate .bar leads are connected to anges on oppositesides ,ofsaid gap.

2,641,682 McKenna ---.v June 9 1953 

